Effectively directing or otherwise controlling effluent output is central to ostomy devices designed to protect skin adjacent to the discharge area. Creating a seal around a person's stoma, such that the seal is dependable, comfortable and conducive to body tissue, is important for the function of ostomy appliances. Once this seal has been made, the appliance may use one or more of a variety of techniques for managing stomal discharge. The formation of such a seal remains an area of continuous improvement and development, since the performance and comfort of the seal is fundamental to customer acceptance. The protection of the external peristomal tissue where the normal skin and stoma tissue meet is an essential characteristic of such an ostomy device. Peristomal tissue can be extremely sensitive. Irritation can result if the peristomal tissue is exposed to body waste, or to repeated application and removal of adhesive or other sealants.
Ideally, the stoma should protrude from the abdominal surface of the ostomate by a distance ranging from 0.5 cm to 2.5 cm. This protrusion forms a spout, from which effluent can discharge directly into the pouch. However, in many cases, the stoma protrudes by a lesser amount or not at all. For example, a “flush stoma” is a condition when the stoma reaches only as far as the surface of the abdomen; a “recessed stoma” is a condition when the stoma does not even reach the surface of the abdomen, and the peristomal skin is drawn into a funnel shaped mouth between the stoma and the abdominal surface. There are many potential causes for these conditions. These can include improper formation of the stoma by the surgeon; and post-operative weight gain by the ostomate. Post-operative weight gain causes the ostomate's abdominal region to expand in girth while the length of the intestine attached to the abdomen remains fixed, thereby resulting in the stoma being pulled toward and ultimately below the surface of the abdomen.
Flush and recessed stomas can be difficult to manage, because some effluent discharged from the stoma can tend to pool around the stoma, instead of the effluent discharging completely into the pouch. Stool retained in this manner can attack the interface between the adhesive body fitment and the ostomate's peristomal skin. Such attack reduces the adhesion of the body fitment to the skin, thereby reducing the effectiveness and the usable life of the appliance. The stool can also cause irritation and degradation of the peristomal skin itself. Stool exiting the stoma may contain digestive juices from the body, and such juices can attack the peristomal skin resulting in excoriation. It is hitherto not known for a single device to accommodate varying distances between the stoma and skin level.
Some known devices use a single expandable balloon or member inside the stoma to form a seal against the inside wall of the opening, and a fixed stop or surface against the outside of the body. However, such devices have to be designed carefully to avoid the risk of damage to the sensitive internal tissue. In such designs, a relatively high concentration of force may be placed on the tissue underneath the stoma, effecting blood circulation in the area under pressure, thereby over time leading to tissue necrosis.
By way of example, U.S. Publication No. 2003/0220621 describes a valved ostomy device including a hollow discharge tube and anchoring means for anchoring the tube in the stoma. The anchoring means comprises an inflatable balloon cuff inserted in the stoma to anchor the tube against the stomal wall, and a screw threaded clamp as an outer stop surface. Although the screw threaded clamp has a conformable pad, the anchoring means bears the entire weight of the ostomy appliance and any collection device attached to it. Thus, the strength of the attachment has to be offset against limitations on the clamping force which can be applied through the peristomal tissue without causing discomfort and tissue damage, and the inflation pressure of the balloon cuff without causing internal tissue damage to the stoma lumen. Additionally, the device has very little or no range of adjustment to the varying distance between the underside of the fascia and the skin, limiting the use to individuals whose fascia-skin distance is within the range of the device. Also, the means of inflating the device requires a secondary mechanism such as a syringe or pump to inflate it. To have the user carry around an extra component is inconvenient, and the inflation mechanism may not have a means to control the amount of fluid to be pumped into the device, which brings associated risks of under or over-inflation of the device.
EP 0168967, EP 1346711 and U.S. Pat. No. 4,950,223 describe ostomy ports comprising a single inflatable balloon inserted into the stoma, and an external adhesive wafer for securing the appliance to the skin around the stoma. Such designs are concerned primarily with the formation of a seal inside the stoma lumen. The peristomal tissue is either unprotected or is protected by the adhesive wafer, leaving the possibility that the peristomal tissue may be vulnerable to the conventional problem of irritation and pain resulting from exposure to stool or repeated applications and removals of adhesive. As in the previous referenced device, there are also no significant accommodations for the variation in fascia-skin distance or the fact that a secondary component is required for inflation.